1. Field of the Invention
This invention relates to a process and plant for treating water to remove volatile ionizable components, specifically a volatile acid and a volatile base. It is particularly suitable for treatment of sour water to remove ammonia, hydrogen sulfide and other contaminants.
2. The Prior Art
Conventionally sour water, particularly from refineries, is treated by stripping it with steam. Such a process is capable of producing treated water which meets the present waste water effluent regulations in most countries of the world. It is however expensive to operate because of the large quantity of steam required, particularly at lower concentrations of the contaminants. For instance, to achieve a 50% reduction in the volatile components, very nearly the same quantity of steam will be required whether the initial concentration is in the order of 20,000 ppm or 200 ppm. The effective efficiency, of such steam stripping is thus at its highest at higher concentrations of the volatile components in terms of the quantity of the volatile components removed per kilogram of steam. What is needed is a process for reducing the concentration of volatile components in an aqueous solution to a very low level in a way that is more efficient in its use of energy.